(a) (1) The following described substances, materials, waters or water shall be limited in discharges to the sewerage system to concentrations or quantities which will not harm either the sewers, wastewater treatment process or equipment, will not have an adverse effect on the receiving stream or will not otherwise endanger lives, limb, public property or constitute a nuisance.
(2) The city may lower these limitations where necessary to meet the above objectives. In forming an opinion as to acceptability, the city will give consideration to such factors as the quantity of subject waste in relation to flows and velocities in the sewers, materials of construction of the sewers, the wastewater treatment process employed, capacity of the wastewater treatment plant, degree of treatability of the waste in the wastewater treatment plant and other pertinent factors.
(b) The limitations or restrictions on materials or characteristics of waste or wastewater discharged to the sanitary sewer which shall not be violated without the approval of the city are as follows:
(1) Wastewater having a temperature higher than 150°F (65°C);
(2) Wastewater containing more than 25 milligrams per liter of petroleum oil, non-biodegradable cutting oils or products of mineral oil origin;
(3) Wastewater from industrial plants containing floatable oils, fat or grease;
(4) Any garbage that has not been properly shredded (see § 15-402). Garbage grinders may be connected to sanitary sewers from homes, hotels, institutions, restaurants, hospitals, catering establishments or similar places where garbage originates from the preparation of food in kitchens for the purpose of consumption on the premises or when served by caterers;
(5) Any waters or wastes containing iron, chromium, copper, zinc and similar objectionable or toxic substances to such degree that any such material received in the composite wastewater at the wastewater treatment works exceeds the limits established by the city for such materials;
(6) Any waters or wastes containing odor-producing substances exceeding limits which may be established by the city;
(7) Any radioactive wastes or isotopes of such half-life or concentration as may exceed limits established by the city in compliance with applicable state or federal regulations;
(8) Quantities of flow, concentrations, or both which constitute a slug as defined herein;
(9) Waters or wastes containing substances which are not amenable to treatment or reduction by the wastewater treatment processes employed, or are amenable to treatment only to such degree that the wastewater treatment plant effluent cannot meet the requirements of other agencies having jurisdiction over discharge to the receiving waters; and
(10) Any water or wastes which, by interaction with other water or wastes in the public sewer system, release obnoxious gases, form suspended solids which interfere with the collection system, or create a condition deleterious to structures and treatment processes.
(Ord. 786, passed 2-1-1977)